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Picked up some 1 1/4" tubing yesterday and spent most of today engineering my new exhaust on the fly. It sure is UGLY!:eek: I still need to go back and clean up the welds as much as possible but everything seems solid and despite a few visible blowouts in the welds, the joints seem sound and solid. I also have to fab the left-side clamp. Since I don't have a servicable 1 1/2" hole saw, the clamps cut from 1/4" plate are the hardest part. The pipes will angle up (from where they are) to a two-into-one silencer just below what would normally be fender level. I have some other fabrication involving the frame to do so the rest will have to wait a while to see just where it needs to run. It sure is ugly though. Did I mention that already. :grin: I guess I'll have to wrap em. ;)

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Ugly or not, I applaud your pluck and adventurous spirit, sir!
 

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Discussion Starter #6 (Edited)
Ugly or not, I applaud your pluck and adventurous spirit, sir!
Thanks. If you look carefully at the two farthest rearward welds on the bottom pipe you can see that I was finally :-? getting the settings and technique figured out. Those two aren't so bad. I used 60* cuts but still worry about the flow (of exhaust). What if any effect will these abrupt direction changes have on exhaust waves? Like several other experiments on this project, I'll never know till it's all finished. Just out of curiosity, I lifted the engine completely off the bench by the one pipe that is clamped to the jugs. It is solid!
The cadmium plating on the pipe didn't help. :( Between the smoke/fumes and the film it leaves on my lens, seeing the joints during welding became pretty iffy a few times. Stubbornness kept me from stopping and cleaning the lens as often as I should have. :cool: Live and learn. At worst, I have my time, some electric and maybe $15 in shop supplies invested. Everything else came from the scrap bin. If it doesn't work, oh well. ;)

BTW, While this was cheaper than a $100+ off the shelf exhaust, my motivation was design. To purchase an exhaust like I want, I'd have to pay someone else to make it anyway so I figured I'd give it a shot! :grin:
 
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Yes certainly try every project you can imagine!
This is just a first draft, the experience you gained here will greatly benefit the next exhaust system you build.

When I start a side project like this, and there have been at least 9 so far during my current bike build...
I keep all of my written notes in old-fashioned composition books, notes, sketches, designs, part numbers, dimensions, etc, so I can look back on it later. Did you happen to note your welder settings for later use?
 

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Yes and no. I do keep notes. Unfortunately I don't keep them very organized when I'm going on the fly like this. I try to come back and do that later - if it worked. ;)

Welder settings were a huge issue because it was not consistent. Since the joints did not always match up flush all the way around, I'd end up with a protruding edge. When welding by that I typically ended up with a gob of metal or blew through the pipe and had to weld it closed... resulting in a gob of metal. The obvious answer of course is to grind those edges down BEFORE trying to weld them. I know that now. :grin:

Yes. It is a learning experience. I spent a whole afternoon trying to come up with a simple way to make the flanges on the head pipe and clamp sleeves. Then it occured to me to simply wrap 3/16 rd. rod around the lip, weld it in place and grind it flush. Every "mistake" is an opportunity to learn. :cool: It can be really frustrating sometimes, but only when you begin taking yourself too seriously.

As Ray Wylie Hubbard said, "I try to keep my gratitude higher than my expectations."
 

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Got the pipes cleaned up a bit this morning. Still not as pretty as a professional with a couple thousand dollars worth of TIG equipment, but I'm satisfied for a rank amataure with a cheap MIG welder in the shed out back. :grin:

The welds penetrated beautifully. After grinding (mostly) smooth I found two tiny pinholes that were easily repaired but the overall pipes are as solid as if they'd grown in that shape. I dressed the clamp collar while it was apart and laid out the shape to cut the second one, but I'm out of time for today. Maybe tomorrow I can get back to it and post some updated photos.

Boys and girls, never be afraid to try. My Dad never told me I couldn't do anything (unless it was illegal or immoral... and that wasn't always obeyed either :-? ). My brothers and I were encouraged to think and solve problems. Sure we were also encouraged to recognize limitations, but not defeat. I sure miss that old man. :(
 
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Boys and girls, never be afraid to try. My Dad never told me I couldn't do anything (unless it was illegal or immoral... and that wasn't always obeyed either :-? ). My brothers and I were encouraged to think and solve problems. Sure we were also encouraged to recognize limitations, but not defeat. I sure miss that old man. :(
Right on man! I built a 2-1 exhaust back in November for my 70 CL350 after looking for months for the elusive Hooker Exhaust that I probably couldn't afford even if I found it. I had also found the Bengie's 2-1 exhaust for the CB/ CL350 but $600 was still more then what I wanted to spend. I ended up building my exhaust with a mig welder as well and while my joints are ugly, there was full penetration and I was wrapping them anyway.

Of note: I read tons of articles on building exhaust, mostly from Cone Engineering but I'm sure there were others. All talked about keeping the radius's as smooth as possible. I used 15 degree pie cuts on my exhaust. I have 2 45 degree bends and each are built with 3 pie cuts each keeping the bends as smooth and "round" as possible. I'd just be a little worried about the 60 degree angles but as you pointed out, you are aware they may be an issue.
 

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Thanks mountaingoat. I suppose my cuts would actually be termed 30 degrees (each end), 60 degrees for each section. Still double what you used. The main reason I used them is because I didn't have an effective way to hold shorter sections of pipe. I don't have a (metal) bandsaw or even a chop saw. For whatever reason I can't seem to end up with a smooth cut all the way around with an angle grinder. Always running out one way or the other, so I used a reciprocating saw to make the cuts. That violent action of course requires a firm hold and the thin wall tubing can't be clamped too tightly. It's a trade off, but I'm hoping for the best. I read some, watched videos and have a friend who's made quite a few, but he is an accomplished (professional) welder with applicable equipment. He'd have probably helped me out but I didn't want to impose and especially, I just wanted to see if I could. Time will tell. This whole bike is becoming one huge mishmash of experiments. I'm kind of looking forward to which work and which don't. :cool:
 

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You do know they make kits for exhaust systems right? :)
 

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carve a block of wood to fit inside end of pipe to prevent it being crushed when clamping. Do you have a vice to hold it? You've got a welder so you could make a chain wrench to hold pipes with less damage
 
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It will be interesting to see what happens. I'm with PJ in that I think it will be tough to get running properly but you do have that ace up your sleeve...it"s a Honda, so it will run and you know it won't be the first with a less than ideal exhaust system.

For future reference, almost any good muffler shop can bend and flare header pipes. I have a bunch of fairly strong flat magnets that I use to hold metal in place when I weld. If your going to be welding magnets a very handy. I've even glued some together to be able to hold right angles

Before I had a chop saw I used 2 pieces of dimensional wood screwed to a piece of plywood, 2 pieces of metal holed strapping and some inner tube rubber, to cut pipe. The dimensional, about 1/2 the thickness of the pipe diameter, is screwed down to the plywood so the pipe can sit between. Use the strapping with the rubber underneath, screwed to the dimensional, to hold the pipe firmly. Follow your mark while cutting the top portion and then use the ends of the dimensional to keep you square through the bottom. If your saw is variable speed then take it slow.
 

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It's possible to buy bends and "donuts " from places that do exhaust pipe work. Probably from ebay as well. For a lot less welding you can make a pretty neat exhaust system.
 

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Discussion Starter #18
I could buy a complete exhaust. That kinda defeats the challenge though. ;)
 
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Please make sure you are in a well ventilated area when weldin that stuff, the fumes n smoke comin off that is poisonous and should not be taken lightly, I’ve fallen victim to it a couple times in my stupider days and it ain’t fun!
 

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Please make sure you are in a well ventilated area when weldin that stuff, the fumes n smoke comin off that is poisonous and should not be taken lightly, I’ve fallen victim to it a couple times in my stupider days and it ain’t fun!
Yeah. it's pretty nasty. I've dealt with coated hardware many times before but never so much and for so long as this project. I was surprised at the film it put on my lens. In all honesty, when cleaning the welds I believe it was the cadmium plating that created much of the slag and ugliness. I'm not a particularly experienced welder, but that stuff cooking off the pipe is not much help. Better than the old galvanized coatings that pop and spew molten globs of zinc and iron in every direction - usually at you - but cadmium is one of those nasty "heavy metals" that shows up in water pollution reports all the time. It has chemical and mechanical properties that are very useful to man's goals, but physically, medically, not so much. ;)

In retrospect, and a point I will take into consideration if I decide to try this again or re-make these once all is done, is to run the joints over the band sander a bit to at least reduce the amount of plating before welding. It is a suggestion I would highly recommend to anyone who decides to try it themselves. Wertzservices advice about ventilation should STILL be observed even then.
 
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